Changes between Version 5 and Version 6 of SAT-with-UAS-Linux

Timestamp:

Aug 8, 2019, 12:38:58 AM (5 years ago)

Author:

Nathan Stratton Treadway

Comment:

Document "Quirks match" flag values in kern.log lines

SAT-with-UAS-Linux

@@ -152 +152 @@
 kern.log line, or in the output from "lsusb".  (In the option strings below, the 4-digit numbers can optionally be preceded a "0x" prefix.) 
 
+
 == Permanent Flag Settings ==
 
@@ -184 +185 @@
 }}}
 
+For more information, see the introduction to the [https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html Kernel Parameters] document, as well as documentation for your specific Linux distribution.
 
 == Temporary Settings ==
 
-If you would like to temporarily set the quirks flag rather than making a permanent change (e.g. in order to run smartctl manually at some point but continuing to use UAS mode normally when using the drive for data transfers), you can do so by dynamically updating the module configuration.
+If you would like to temporarily set the quirks flag rather than making a permanent change (e.g. in order to run smartctl manually at some point but continuing to use UAS mode normally when using the drive for data transfers), you can do so by dynamically updating the module configuration (also described in the introductory paragraphs of the Kernel Parameters document).
 
 First, unmount/unplug the USB device, then run the following commands (as root):
@@ -208 +210 @@
 # echo "" > /sys/module/usb_storage/parameters/quirks 
 }}}
-to clear the configuration for the next time the device is plugged in.
+to clear the configuration (i.e. use the kernel's compiled-in defaults) for the next time the device is plugged in.
 
 == Useful Links ==
@@ -219 +221 @@
 
 Examples of the problems that originally triggered the current kernel behavior: 
-* [https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1584557 Seagate external drive causes SCSI bus resets when UAS enabled]
+* [https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1584557 Ubuntu Bug: Seagate external drive causes SCSI bus resets when UAS enabled]
 * [https://unix.stackexchange.com/questions/441668/debian-usb3-hdd-uas-i-o-errors StackExchange: Debian + USB3 HDD + UAS: I/O errors]
 * [https://unix.stackexchange.com/questions/418326/how-do-i-make-my-seagate-2tb-usb-hdd-work-in-linux StackExchange: How do I make my Seagate 2Tb usb hdd work in Linux?]
 
-When using usb-storage quirks to override 
+"Quirks match" kern.log lines:
+
+* The final number on the  `Quirks match for vid 0bc2 pid ab38: 800000` kern.log line represents the set of flag bits that have been enabled (by the "quirks" option processing) for this particular USB device.  (Note that the USB id numbers as well as the flag value are shown in hexadecimal.)
+* For SAT pass-through issues, the important flags are 
+   || IGNORE_UAS || 0x00800000 || :u ||
+   || NO_ATA_1X  || 0x02000000 || :t ||
+* The full list of flag bits is defined in the [https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/usb_usual.h include/linux/usb_usual.h] file in the kernel source (while the quirks-option flag letters and fuller explanations of each flag's meaning are found in the [https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html Kernel Parameters] documentation).